Question

Fill in with or by.
1 Seals are hunted ... killer whales.
2 The oil-covered brids were cleaned .. soap.
3 This environmental problem has been caused .... human carelessness.
4 Levels of pollution can be measured .... this instrument

Answer 1

Respuesta:

Explicación:

1

1) by

2) with

3) by

4) with

2)

are

being

was

being

be

been

be